What would war be like between two "First World" countries?

After reading this question, it got me thinking about what a modern day war between two first world countries, like Britain and Germany or the US and France or something.
Would it be precision strikes against military bases only, or would there be invasion of civilian population centers too? What about embargos and blockades? With the technology of both sides, along with the shared view by both sides of keeping the civilian populace out of harm’s way, what would fighting actually be like, and where would it take place?